Sound record



E. kW. DUKE SOUND RECORD n -June 19, 1934.

Filed Feb. 16, 1933 url o olguoo IETTOL/Qe @am ATTORNEY Patented June 19, 1934 SOUND RECORD Elza W. Duke, Brooklyn, Y., assigner, by mesne assignments, -to W-R-M, Inc., New York, N. Y., a corporation ol' Delaware Application February 1s, 1933, serial No. 657,093-

3 Claims.

- The present invention relates to improvements in sound records and the method of producing the same, lone object of the invention being the provision of a disc record upon which the photo- 5 graphic sound track is disposed spirally thereon and in which thesound characteristics are identical throughout the entire length thereof, that is either variable area or variable density throughout its length.

Another object of this invention is the provision of a disc sound record in which the sound track either of a variable area or variable density type is disposed thereon in such a manner as to produce a sound reproducing device, sound with the same characteristics as to frequencies, as were originally recorded either upon sound-onfilm, a phonic groove disc or through the instrumentality of a microphone or any combination thereof, the sound trackbeing of spiral or convoluted form and being disposed to move at 'the same lineal speed throughout its length regardless of the changingl radii during 'the rotation of the disc. l Still another object of this invention' is the provision of a disk the main body of which is composed of a transparent or translucent cellulose material, such as a nitrate `or acetate celluloid as now used in the film industry, and upon which is placed the necessary sensitized emulsion upon which the spiral sound track is printed and developed, so that light may be projected therethrough similarly to when a regular sound track lm is employed, the disk being further provided with a spiral vrow of sprocket holes, the center line of which connecting all holes is spirally parallel with the sound track throughout its length to provide means whereby the disc may be rotated.

` In the accompanying drawing:-

Figure 1 is a plan view of the sound record disc made accordmg to and embodying `the present invention, a quadrantal section of the sound track only being shown and this particular sound track being of the variable density type.

Figure 2 is a diagrammatic view of one method of optically producing a disc record negative from a sound-on-lm positive or negative.

Referring to the drawing and 'more particularly to Figure 2v thereof, the numeral 5 designates the sound-on-film record which may be of the regular 35 mm. type for the presentexample and which is caused to move continuously and have projected therethrough from the printing lamp 6, vso that the striations from the sound track are optically projected through the film (Cl. 274-4L6) and the optical system 7 upon Ithe desired portion of the sensitized surface 8 of the negative disc record 9. This record is mounted on a slidable support 10 (such as is illustrated in patent to Clay No. 881,664 by way of an example) and as the record itself is provided with the spiral sprocket holes 12, is operated synchronously through sprocket wheel 13 with the sound-onlm mechanism. One method of doing this Withl. slight modification in the mechanism in orderthat the .nlm and the disc may be moved continuously and not intermittently is shown in the patent of Bettini, No. 1,298,282, and more particularly the construction shown in Fig. 2 thereof. The longitudinally disposed sound track of the film is projected to assume a spiral upon the disc and as the linear speed on the disc is identical throughout its length, thefllm sound track is thereby transferred into 'a spiral sound track with the identicaly characteristics on the dise, when the disc is developed in the usual manner.- The body of the disc is of a transparent or translucent material, such as celluloid or the like, -the disc can then be used as a negative.

This negative disc is now superimposed in a printing frame or machine upon the disc 14 to receive the positive sound record. This record as shown in Figure 1 is composed of a supporting body 15 and an emulsion 16 and it in turn isI provided with a similar number of sprocket holes 17 to the negative record. In this manner a positive photograph of the spiral sound track yis transferred to the positive disc and when developed will contain a sound track having the same characteristics as that of the sound film but in spiral formation. l

In order that the proper continuous motion be imparted to the disc during the action of producing sound therefrom, it is essential that the sprocket holes 17 be placed equi-distantly apart o5 and further that an imaginary spiral line run through the centers of all holes, form a spiral which has its convolutions substantially parallel ywith av spiral line imaginarilydrawn through the 'medial center of the sound track.

The disc carrying the-positive sound track is l preferably made of transparent or translucent material, but may be made of opaque material where it is desired to use the sound track by reilection instead of an intermediary between an exciter lamp and an optical system, and a photoelectric cell.

It is apparent from the\foregoing that with a record of this type great economy in space is obtained as a 35mm. sound track of the longitudinal |10 2 type can be readily placed upon a single disc with the convoluted sound track 116 of an inch wide, it being possible to form the spiral either from the periphery to the center or vice-versa.

In reproducing sound froma record of this type from which the body is made of a transparent or translucent material such as the type of celluloid used in iilms at the present time of the nitrate or acetate type, the disc is mounted for rotation upon a sldable pintle and a continuously operated sprocket rotates the disc so that the portion of the sound track to be acted upon passes between the inner end of the optical system and a photoelectric cell. The disc and its pintle are gradually moved to compensate for the increasing or decreasing diameter of thedisc due to the spiral actuating means and thus placing the various portions of the sound track at the proper speed and also exposing or concentrating upon the area to be effected so that the sound is reproduced through an amplifying system and loud speakers similar to the present type sound on nlm amplication.

It is also apparent from the foregoing that the sound track can be of a variable area type, it being necessary only that such type sound track be carried by the film from which it is printed and the negative disc will be, therefore, formed in the same manner as heretofore described and when the same is printed to form a sound record, the spiral sound track printed and developed thereon will be o! the variable area type and will have the same hill and dale characteristics as the sound-on-film.

What is claimed is:-

1. A sound record of circular type in which the sound track is spirally disposed thereon and the said record being provided with a coordinated series of spiral sprocket holes, through the medium of which the disc may be rotated.

2. A sound record having on the emulsion face thereof a spiral photographic sound track, said track being of the same Width throughout its length, and said record being provided with a spiral series of sprocket holes substantially paral leling the spiral sound track.

3. A transparent cellulose photographic sound disc having coordinated spirals of sound track and sprocket holes, and in which lines passing respectively through the medial center of the sound track and through the centers of all sprocket holes would be spirally parallel.

ELZA W. DUKE.

Azo 

